Service t



Dec. ,7, 1943. HENDERSON SERVICE TEE Filed June 29, 1942 Patented Dec.7, 1943 UNITED STATES PATENT OFFICE SERVICE VT Elting Henderson,Whittier, Calif. Application June 29, 1942, SerialNo. 448,979-

2 Claims. (Cl. 251-43) The present invention relates to an improvedservice T arranged to be interposed between a fluid pressure main and abranch or service pipe, for conducting gas, water, oil, and other fluidsfrom the main to the service pipe, and is more particularly directed tothe association with the service T, of a combined plugging unit and toolguide. The present application is a continuation-in-part of mycopendin'g application Serial No. 410,632, filed September 12, 1941.

An important feature of the invention consists in providing the bore ofthe T with an integral web or partition member which is formed with areduced axially disposed openingof such length and diameter relative tothe drill or'a center cating punch, that the wall of the reduced openingacts to constitute an axially disposed guide to insure both the drilltool and the punch, when inserted into the T, being maintained in properoperative alignment relative to the part of the main to be tapped. Thewall of the opening in the web also ccacts with the drill to prevent thelatter from crawling on the main during the drilling operation. The topor upper surface of the web is formed to provide a seat for the end of amovable plug or stopper which is permanently inserted within the T afterthe drilling operation is completed. This plug is normally adjustablymaintained in a position above the web so as not to interfere with thefree flow of the fluid through the T. However, in the event it becomesnecessary to cut off the supply to the service line or pipe, this mayquickly and easily be done by moving the plug in engagement with itsseat.

A further object is to provide an improved apparatus for controlling theflow of the fluid through the T. This is effected by associating withthe valve seat in the T, means including a hollow plug or cylinderhaving its inner and outer surfaces provided with threads of differentpitch, which coact with complementary'formed threads on the inner wallof the T and the outer surface of the stopper, to move the stopperaxially relative to its seat. The differential threaded plug is alsoarranged when rotated relative to the stopper when the latter isinitially moved against its seat, to exert an increasing downwardpressure on the stopper due to the difference in pitch of the threads,to insure the stopper being maintained in tight sealing engagement withits seat when the fluid supply is cut off.

Other objects and advantages of theinvention will become apparent fromthe following description, when taken in conjunction with theaccompanying claims and drawing.

Referring to the drawing, in which are shown several preferredembodiments of the invention:

Figure 1 is a vertical sectional view of the T and the main to which itis applied, and shows a part of a drilling tool associated therewith.

Figure 2 is a vertical sectional view of the T showing a plugging unitassociated therewith.

Figure 3 is a detail vertical sectional view of the upper portion of.the T showing the stopper in its raised'position.

Figure 4is a plan view of Figure 3.

Figure 5 is detail vertical sectional view of a modified form of theinvention, and

Figure 6 is a plan view of Figure 5.

Referring to the drawing, in which like numerals indicate like parts inthe several views, It designates the body of a service T which isconnected to the fluid pressure main H, such as a gas pipeor the like,in any suitable manner, such as by having its lower or inlet end weldedas at lZto the main; Prior to the connection of the T l0, it ispreferably preformed with an axial bore l3 and a lateral port' or outletI4 to which the service line or pipe, not shown, is suitably connected.

The T l0 may be of solid steel forging and is bored inwardly from eachend thereof a specified or predetermined distance, to form the elongatedintegral web or partition l5, which preferably extends from the lateralport I4 downwardly'to a point adjacent the main II to provide the borewith a lower or inlet section l6 and a spaced upper section ll. Thesolid web 15 is then drilled to provide the reduced axially disposedelongated opening 18 so as to establish communication of the inletsection IS with the upper section I! and the outlet port M. The upperend of the T H] has an externally threaded portion l9 and an internallythreaded portion 20.

The preformed T if) is initially installed at the: point where thebranch line or service pipe is to be attached to the main, and adrilling apparatus such as shown in the Mueller Patent No. 1,996,345,April 2, 1935, may then be connected to the Tim order to tap the main.The fitting 21 of the drilling apparatus is internally threaded at itslower end so as to be connected as at 22 to the'externally threadedportion l9 of the T.. The elongated drill 23 which is con. nected as at24 to the rotatable operation rod 25, is then inserted through thefitting 2i and into the T toform the opening 26 in axial alignment withthe bore l3. The reduced opening l8 preferably extends from the outlet14 to a point adjacent the inlet ofthe bore, and is of such a length asto overlap a major portion of the tool inserted therein, in order toserve as a guide to hold the shank of the tool steady during thedrilling operation.

The reduced opening IS in the web i5 is accurately machined or formed toprovide a small tolerance or clearance between the wall thereof and thedrill. It will be manifest that if there is too much clearance betweenthe drill and the wall of the opening IS, the wall would not constitue aguide means or bearing surface which would insure proper alignment ofthe tool with the main during the tapping operation. For; this reason,the clearance between the tool and drill not infrequently has beenbroken in the T due to the excessive strains to which it was sub ject'edduring the drilling o'peration. By virtue of the small clearance betweenthe wall of the opening I 8 and the drill, it will be seen thatpositive, efficient and economical means are provided for guiding andmaintaining the drill in proper alignment with the T' when drilling ahole in the main and which also prevents crawling of the drill on themain. The upper surface of the web 15 at the juncture of the section I!with the reduced opening I8, is preferably formed with a seat or taperedportion 2?, the purpose of which will be subsequently described.

Prior to the attachment of the drilling apparatus to the T to tap themain ii, a center 10- cating punch such as shown in the Muellerapplication, Serial No. 315,825, filed January 26, 1940, may beintroduced into the T to form an indentation in the outer wall of themain to insure the opening being formed concentric with'the bore of theT. The diameter of the centering punch is substantially the same as thatof the'drilling too-1 23 so that the wall of the reduced opening l8 willinsure the punch being maintained in proper axial alignment with thebore of the T. Upon the removal of the punch or indenting tool from theT, the fitting 2| and its associated parts are connected to the upperportion of the T so that the drill 23 may 2 to back up or turn thelatter in a counterclockbe rotated and moved axially into engagementwith the indented portion of the main, and thus insure the drill 23being positioned and maintained concentric with the drilling apparatusand the bore of the T during the tapping operation.

After the opening 26 is formed in the main, the drilling apparatus isremoved from the plugging unit is permanently positioned within theupper section ll of the bore. This plugging unit comprises a hollowremovable closure member or brass plug 28 which is externally threaded.as .at-29, to engage the complementary internal threads 23 on the T. Theclosure member 28 also has an internally threaded opening 33concentrically disposed relative to the axis of the bore i3 of the T.The wall of the opening 33 is arranged to receive and guide the upperthreaded portion or stern 3! of an adjustable stopper or plug 32,preferably made of steel; and which is inserted within.

the T after the-opening. 26 hasbeen forined in the main, in order toprovide mcan's' fi1r'con'-..

trolling or outing. off the fio'w of the fiuidsuri-f ply from the mainto the service pipe when'i't'.

I-Ieretofore in devices of this character,-

;' seat 21.

ter. The stopper 32 is relatively short and is preferably formed with atapered lower end portion 33 arranged to extend a limited distancewithin the openinug H! of the web and engages the seat 21 when it isnecessary to cut ofi the flow of the supply of the surface line so as toform a tight sealing engagement therewith. The top of the stem orportion SI of the stopper 32 may be provided with a kerf or recess 34which receives a suitable tool, such as a screw-driver or the like, soas to control the axial position of the stopper 32 relative to the Thestopper 32 is preferably formed beneath the threaded stem 3! with atapered P inserted in the kerf 3Q.

shoulder 35 arranged, when the stopper is raised to its full openposition, to engage the lower end of the opening 38 in the plug 28 (Fig.3) in order to prevent leakage of the fluid therethrough. The upper endof th plug 28 extends from the T and has a reduced portion or head 36 ofany'polygonal shape for receiving a tool such as a wrench, so as toapply Or remove the plug from the T.

When the stopper 32 is moved downwardly against its seat 2? to cut ofithe flow of gas through the T, it has been found that it is not possibleto apply sufiicient pressure on the stopper by a screw-driver insertedin the kerf 34, efiectively to seal the gas flow through the T.Accordingly, the threads 23 and their coacting threads 29 on the plug 28are of different pitch than the threads 30 and their coacting threads 3!on the stopper 32. As shown in Figure 2, the threads 2023 are I l-pitch,While the threads 33-3! are 13-pitch. The internal threads on the plug28 and their coacting threads on the stem of the. stopper 32 may be ofgreater or less pitch than the external threads on the plug and theircoacting threads on the T.

When it is desired to out ofi the flow of the gas through the T, thestopper 32 is rotated clockwise as shown by the arrow A in Figure 4 soas to be forced downwardly as tightly as possible against its seat 2'!by a screw-driver or th like, This pressure alone would not besuilicient to insure the stopper being maintained in sealing engagementwith its seat. Therefore, a suitable tool, such as a wrench, is appliedto the head 33 of the plug 28 wise direction (arrow B, Figure 4),whichtends to unscrew the plug 28 from the T 53 at the rate of /14" perrevolution. Since the internal threads 30 and their coasting externalthreads 3! on the stem are /13 pitch, it will be seen that,

due to the differential effect of the pitch of the threads 23-29 and3il3l, the plug 23 will tend to come off or be removed from the stopper32 at a faster rate than it can be unscrewed from the T l3, with theresult that the plug 28 exerts a downward increasing thrust or pressureon the stopper 32 equal in effect to a fine thread, the equivalent ofthe diff rences in the pitch of the threads 25-29 and 33- --2!. Thus,positive means are provided to insure the stopper being held against itsseat irrespective of the pressure of the fluid in the main. Moreover,since the head 36 of the plug 28 may be engaged b a wrench'or other toolhaving a good leverage, a much greater force can be exerted on thestopper to insure the latter being moved and maintained in; tightsealing contact withits seat 21.

. lnthe modification shown inFigures 5 and 6, thg pitch of thethreadsare reversed to that previously disclosed. ln other'words, the externalthreads 31 on the plug 38 and their complementary internal threads 39 onthe inner wall of the T 40 are of l3-pitch, while the internal threads4| of the plug and their coacting external threads 42 on the stem of thestopper 43 are of i l-pitch.

To cut off the flow of the fluid from the T 40, the stopper 43 isinitially turned in the direction of the arrow C (Figure 6) so as to beforced in engagement with its seat, by a tool inserted in the kerf oropening 44 sufiiciently tight so as not to be rotated when the plug 38is moved relative thereto. After the stopper has been seated, a suitabletool is applied to the head 45 of the plug 38 and the latter is rotatedin a clockwise direction or the same direction in which the plug hasbeen turned, as shown by the arrow D in Figure 6, to engage its seat, inorder to exert a downward increasing pressure on the stopper due to thedifference in pitch of the threads, and thus insure the stopper beingfirmly maintained in sealing engagement with its seat. It will be notedthat the only substantial difference between the threaded arrangementshown in the form of the invention disclosed in Figure from that shownin Figure 2, is that in the former the plug is rotated in acounterclockwise direction, or opposite to the direction or rotation ofthe stopper while in the latter it is turned in the same direction toforce the stopper against its seat.

In both forms of the invention, the flow of the fluid through the T iscontrolled by, first, threading the stem of the stopper to the plug,then inserting the plug and stopper into the T so that the plug isthreaded to the T above the valve seat. While, normally, the stopper ismoved away from its seat to allow the free flow of the fluid through theT, it will be seen that upon the stopper being moved downwardly by asuitable tool, it will be brought into sufficiently tight engagementwith its seat, as to be prevented from rotating with the plug when thelatter is turned to increase this downward pressure. The plug is theneither turned in the same direction or in the opposite direction to thatof the stopper, depending upon the pitch of the threads, and is movedrelative to the stopper to exert an increasing downward pressure on thestopper due to the difference in pitch of the threads, which furtheracts to provide sufficient lock-off pressure to insure the stopper beingaccurately and firmly seated against its seat so as to be capable ofwithstanding the pressure of the fluid to which Ts of this type arenormally subjected.

It will be understood that the several forms of the invention and methodfor controlling the flow of the supply through the main are merelyillustrative of preferred embodiments, and that such changes may be madewithout departing from the spirit of the invention, as come within thepurview of one skilled in the art and the scope of the appended claims.

I claim:

1. A T for connecting a fluid pressure main to a service pipe, said Thaving an axial bore and a lateral port and provided with an internallythreaded end portion, said bore having a web provided with an axialopening and a seat, a stopper in the T arranged to engage said seat tocut off the flow of the fluid through the T, said stopper having anexternally threaded stem, an externally threaded plug connected to thethreaded portion of the T and having a central threaded openingconnected to the threaded stem of the stopper, the internal threads onthe plug and the external threads on the stopper being of differentpitch than the external threads on the plug and the internal threads onthe T, said stem having means for receiving a tool to move the stopperinto and out of engagement with said seat, said plug having a toolreceiving portion whereby when the stopper has been initially moved infirm engagement with its seat, and the plug is rotated relative thereto,the movement of the plug acts to exert a downwardly increasing pressureon the stopper due to the difference in pitch of the threads to insurethe stopper being maintained in tight sealing engagement with its seat,and means on the stopper for engaging the wall of the opening in saidplug when the stopper is moved away from said seat, to prevent theescape of fluid through said opening.

2. A T for connecting a fluid pressure main to a service pipe, said Thaving an axial bore and a lateral port and provided with an internallythreaded end portion, said bore having a web provided with an axialopening and a seat, a stopper in the T arranged to engage said seat tocut off the flow of the fluid through the T, said stopper having anexternally threaded stem, an externally threaded plug connected to thethreaded portion of the T and having a central threaded openingconnected to the threaded stem of the stopper, the internal threads onthe plug and the external threads on the stopper being of differentpitch than the external threads on the plug and the internal threads onthe T, said stem having means for receiving a tool to move the stopperinto and out of engagement with said seat, said plug having a toolreceiving portion whereby when the stopper has been initially moved infirm engagement with its seat and the plug is rotated relative thereto,the movement of the plug acts to exert a downwardly increasing pressureon the stopper due to the difference in pitch of the threads to insurethe stopper being maintained in tight sealing engagement with its seat,and said stopper having a tapered shoulder arranged to engage the plugto close the opening therein, when the stopper is moved to its full openposition.

EL'IING HENDERSON.

